Aerial survey of land and sites around Sherborne

Parkland laid out deliberately, with a lake, planted clumps, a drive and long views arranged between them, is a different thing from farmland with trees in it. The layout is the asset, and from above the whole composition reads at once: what has silted, what has grown out, where a planting has failed and where a view has closed in.

That is the usual reason for a capture here. It goes on file as a dated record for whoever manages the place, and where the estate is planning work it becomes the base for the discussion rather than a set of photographs taken from the ground on different days in different light.

Old ground here carries earthworks: platforms, banks, ridges, hollow ways, the outlines of things that were built and taken away. A flight in flat overhead light will barely show them. The same ground flown in low winter sun, with the shadows raking across it, shows them clearly.

So a survey aimed at earthworks is booked for the season and the time of day rather than squeezed into whatever slot is free. It is one of the few cases where the flying conditions people usually avoid are the ones you want, and it costs nothing to plan for once somebody has said what the survey is for.

Ornamental water is a common feature of estates in this country, and water is where a camera-based survey stops. A lake surface reconstructs poorly or not at all, and nothing below it reconstructs, so the model shows banks, margins and structures with a hole in the middle.

Marked as such, that is a perfectly useful product: extent on the day, the state of the margins, silting at the inflow, the condition of a dam or a sluice. Presented without the caveat it would be misleading, so the caveat goes in the report every time.

The building stock here is exceptional and complicated: abbey, school and townhouse roofs with lead, parapets, valleys and hidden gutters in quantity. A land survey that includes buildings inevitably captures those, and the plan view is often the first clear look anyone has had at them.

That is a by-product and it is described as one. A proper condition inspection of a lead valley is a different job with a different site in this group, and the report here says what it is: a dated record of the roofscape as part of a wider capture.

North Dorset is inland, sheltered and drier than Devon, and the flying calendar here is noticeably kinder. Winter days that would be unusable on the moor edge are perfectly workable in this valley.

That matters for anything time-sensitive. If a capture has to happen inside a particular fortnight, this is the sort of country where that is a reasonable request rather than a hopeful one.